GM1 gangliosidosis, ceramide lactoside lipidosis, Morquio B disease, Krabbe disease, Fabry disease, Gaucher disease, Tay-Sachs disease, Sandhoff disease, fucosidosis and the like are conventionally known as glycolipid metabolic disorders. These diseases are diseases which are generated as a result of causing mutation in various glycolytic enzymes. Among them, GM1 gangliosidosis, Morquio B disease, ceramide lactoside lipidosis and Krabbe disease are diseases which are generated when β-galactosidase loses its enzyme activity by undergoing mutation, and Gaucher disease is a disease generated when β-glucosidase loses its enzyme activity by undergoing mutation Carba-sugar amine derivative are known as substances which have a possibility of becoming medicaments for these diseases (International Publication WO 03/022797).
The carba-sugar amine derivatives described in International Publication WO 03/022797 have a function to recover reduced or lost activity of a mutated enzyme, but being considerably low in their solubility in water, it could not be said that they are sufficient for using as medicaments.